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        <td class="header">&nbsp; Phase to Height conversion (InSAR operator)</td>
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<h3>Phase to Height conversion</h3>

<p>
    This operator converts the unwrapped interferometric phase to the heights in the radar coded system. This
    functionality is sometimes referred to as "slant-to-height" conversion.
</p>

<p>
    Implementation is performed following the Schwabisch method, that uses polynomials to compare the actual phase with
    the flat earth (reference) phase.
</p>

<p>
    The Schwabisch method, is a fast method that yields the radar coded heights. It builds on the idea to first
    compute the reference phase at a number of discrete heights and then to compare the actual phase from the
    interferogram with these pre-computed values to determine the height.
</p>

<p>
    An obstacle with this method is that the interferograms that are used as input do not contain the reference
    phase anymore, so that has to be pre-computed and included in the height-estimation procedure.
</p>

<h4>Operator parameters:</h4>&nbsp;&nbsp;

<ol>
    <li>
        <b>Number of estimation points:</b> The number of locations to compute the reference phase at different
        altitudes.
    </li>
    <li>
        <b>Number of height samples:</b> Number of height samples in range [0,5000) at which the reference phase will be
        estimated.
    </li>
    <li>
        <b>Degree of 1D polynomial:</b> Degree of the one-dimensional polynomial to "fit" the reference phase through.
    </li>
    <li>
        <b>Degree of 2D polynomial:</b> Degree of the two-dimensional polynomial to fit the reference phase through.
    </li>
    <li>
        <b>Orbit interpolation degree:</b> Defaults to a polynomial of degree (number of state vectors)-1, but smaller
        than degree 5.
    </li>
</ol>

<h4>Source Products:</h4>&nbsp;
<!--&nbsp;-->
<p>
    Unwrapped interferometric product.
</p>

<h4>Output bands:</h4>&nbsp;
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<p> The height estimated from the unwrapped interferogram. The heights are stored meters, while 0.0 height indicates
    the problem with unwrapping.
</p>

<!--<h4>Implementation notes:</h4>&nbsp;-->
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<!--<p><i>(More details on algorithmic implementation COMING SOON!)</i></p>-->

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